begin
{$IFDEF VER200}
ShowMessage('这是 Delphi 2009');
{$ENDIF}
{$IF DEFINED(VER200)}
ShowMessage('这是 Delphi 2009');
{$IFEND}
end;

begin
{$IFNDEF VER150}
ShowMessage('这不是 Delphi 7');
{$ENDIF}
{$IF NOT DEFINED(VER150)}
ShowMessage('这不是 Delphi 7');
{$IFEND}
end;

begin
{$DEFINE AAA}
{$DEFINE BBB}
{$IF DEFINED(AAA) OR DEFINED(BBB)}
ShowMessage('条件标识符 AAA 和 BBB 其中一个定义了');
{$IFEND}
{$IF DEFINED(AAA) AND DEFINED(BBB)}
ShowMessage('条件标识符 AAA 和 BBB 都定义了');
{$IFEND}
end;

begin
ShowMessage(FloatToStr(CompilerVersion)); {在 Delphi 2009 中, CompilerVersion = 20.0}
{$IF CompilerVersion >= 17.0}
ShowMessage('这是 Delphi 2005 或以上的版本');
{$IFEND}
end;

begin
{$IFOPT B+}
ShowMessage('指令 B 已打开');
{$ELSE}
ShowMessage('指令 B 已关闭');
{$ENDIF}
{$B+}
{$IFOPT B+}
ShowMessage('Ok!');
{$ENDIF}
end;